Fixes for D-001验收问题:
1. test-quick.sh: use set -euo pipefail, uv run ruff, no tail pipe
2. Remove unused imports in factories (app.py, platform.py, provider.py)
3. Fix unused variable in smoke test
4. Add noqa: E402 to test_n8nsvapi.py lazy imports
5. Update smoke test docs: "minimal fake flow" not full pipeline
Now test-quick is a reliable gate: lint failures exit 1, test failures propagate.
Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>